SWCC P1177 Dumbleyung detailed ppm thorium grid geodetic

The radiometric, or gamma-ray spectrometric method, measures the natural variations in the gamma-rays detected near the Earth's surface as the result of the natural radioactive decay of potassium (K), uranium (U) and thorium (Th). The data collected are processed via standard methods to ensure the response recorded is that due only to the rocks in the ground. The results produce datasets that can be interpreted to reveal the geological structure of the sub-surface. The processed data is checked for quality by GA geophysicists to ensure that the final data released by GA are fit-for-purpose.This radiometric thorium grid has a cell size of 0.00021 degrees (approximately 21m) and shows thorium element concentration of the Dumbleyung (SWCC), WA, 2008 in units of parts per million (or ppm). The data used to produce this grid was acquired in 2008 by the WA Government, and consisted of 75805 line-kilometres of data at a line spacing between 100m and 400m, and 60m terrain clearance.

辐射测量法（radiometric，又称伽马能谱法（gamma-ray spectrometric method））通过探测地球表面附近的伽马射线自然变化，表征钾（K）、铀（U）与钍（Th）的天然放射性衰变所产生的辐射响应。所采集的数据将通过标准化流程进行处理，以确保记录的响应仅源自地下岩石的辐射。经处理后得到的数据集可通过解译，揭示地下地质构造特征。经处理的数据将由GA地球物理学家开展质量核验，以确保GA发布的最终数据符合使用要求。
本辐射测量钍网格（radiometric thorium grid）的单元格大小为0.00021度（约合21米），展示了2008年西澳大利亚州（WA）邓布尔云（Dumbleyung，SWCC）的钍元素浓度数据，单位为百万分率（parts per million，简称ppm）。用于生成该网格的数据由西澳大利亚州政府（WA Government）于2008年采集，总测线长度达75805测线公里，测线间距介于100米至400米之间，观测高度距地表60米。